imap_ping

(PHP 4, PHP 5, PHP 7)

imap_ping — Check if the IMAP stream is still active

Description

boolimap_ping
( resource$imap_stream
)

imap_ping() pings the stream to see if it's still
active. It may discover new mail; this is the preferred method for a
periodic "new mail check" as well as a "keep alive" for servers which
have inactivity timeout.